Engine-pressure-recording instrument



Dec. 14 1926.

H, CAMINEZ ENGINE PRESSURE RECORDING INSTRUMENT 2 Sheets-Sheet 1 Filed May 1'7, 1923 Q & avwawtoz liarvld Canines 3&1

W? 81mm;

Dec. 14 1926.

' H. CAMINEZ ENGINE PRESSURE RECORDING INSTRUMENT Filed May V17. 1925 2 Sheets-Sheet 2 gnvenhot Patented Dec. 14, 1926.

UNITED STATES HAROLD GAMINEZ, OF DAYTON, OHIO.

ENGINEPRESE5URE-EECOEIDING INSTRUMENT.

Application filed May 17.

This invention relates to an engine pressure recoroi instrument, the same being adapted for use in connection with the cylinder and piston of any engine for the purpose of making a record of engine pressure.

The object of the invention is to provide an instrun'ient which will directly produce a diagram of the pressure chan that occur in the cylinder of an engine during a cycle operations extending over a period of time. The improved instrument will operate under the present day high engine speeds because in its design the inertia and friction effects on pressure indications have been almost entirely eliminated. The inument is a rugged mechanical device and therefore possesses a decided advantage over the delicate optical instruments heretofore employed for the same duty.

The invention consists in the features of construction, combination and arrangement herein fully described, illustrated and claimed.

In the accompanying drawings:

Figure 1 is a vertical diametrical section through the instrument.

Figure 2 is an end elevation of the same.

Figure 3 is a bottom plan view thereof.

Figure l is a horizontal section through the instrument on the line BB of Figure 1 looking downwardly.

Figure 5 is a transverse section on the line AA of Figure 1 looking downwardly and showing the tongue guide in concentric position.

Figure 6 is a view taken on the same line but showing the tongue guide in eccentric position.

Figure 7 is a plan view of the collar which yoltes the together.

Figure 8 shows the appearance or a re cord card utter a record has been drawn thereon by the instrument.

Tn the improved recording ii'istruiuent, the reciiird card is carried on a drum which reabout a central barrel as will hereinafter appear. This drum it is preit'erred to drive at engine camshaft speed, altho this not essential. The instrument has an automatic reed mechanismwhich shifts the card drum carrier along its longitudinal a. a small distance in'every revolution of the drum. The appearance of the card produced by the instrument is graphically shown in Figure 8.

Referring now to the drawings, the frame 1923. Serial No. 639,579.

of the instrum nt designated at 1 comprises an ei-tternal threaded plug like extension 1 which is adapted to be screwed into the engine c\ inder (not shown), for example in one oi the spark plug holes. lllounted within he plug 1 is a reciprocatory piston 2 which is acted upon by the gas pressure in the engine cylinder. The piston 2 is held down by a. coil expansion spring 3 bearing upon the flange oi the piston 2 the travel. of the piston 2 being limited by a stop nut threaded into a barrel 12 which is an integral part oi the frame l The position of the nut 4: is adjustable and the adjustment may be maintained by a jam nut 5. The motion of the piston 2 is transmitted to a pencil or stylus 8 by means or" a short twoarmed lever 6, pivoted as shown and engaged in a slot in the flange of the piston 2, and in a similar recess in the hell crank lever 7 as dearly shown in the Figure 1, the proportions of the levers 6 and 7 being such as to magnify the motion of the piston sulficient to allow the pencil 8 to bear against a record card which is held by suitable clips 8 on the drum 9.

The height of the drum 9 is determined by the position of a drum carrier 10. Drum carrier 10 is threaded upon and surrounds the barrel 1? so that the height of the drum carrier is varied by rotating the same. The position of the drum carrier 10 also determines the position oi? a spring compressor 1.1. A dii'l'erential screw adjustn'ient is employed whereby the travel of the spring compressor 11 is proportional to, but less than that of the drum carrier 10. This action is obtained by providing the spring compressor 11 with one or more projections 11 having a sliding fit in grooves or guideways 11 in the barrel 12, so that the spring compressor can not rotate with respect to said barrel. The upper end of the spring compressor spindle is slotted as shown in F 1 within which the tongue guide 39, described later, opera The slotted end er the spindle 11 extends into the hollow shaft 27 when in the position shown in Fig. 1.

The spring compressor spindle is threaded into the head l0 of the drum carrier. This thread is of a liner pitch than the threadon he barrel 12 on which the drumcarrier 10 moves. lVith the above arrangement, if the spring compressor spindle 11 is provided with sixteen threads per inch while the bar- Ill) rel 12 is provided *ith twelve threads per inc 1, then when the drum carrier is rotated twelve turns it moves on the barrel one inch, while the spring compressor spindle 11 is drawn up into the drum carrier head 10 a distance of twelve divided by sixteen or three-fourdis of an inch. The mov mentof the spring compressor 11 with respect to the barrel 1.2 for a vertical travel of one inch of the drum carrier 10 therefore one n inus three-fourths of an. inch which is equal to onc-fo rth of an inch.

The drum 9 is formed witii a gear face 13 which meshes Wlill a near ll on and driven by a tubule shaft The gear 14 is held in mesh with the gear face 1 collar 16 rating the general meral S as shown in Figur bore of the shaft is another 5.

may be driven at camshaft ced either through su lie connection 8 with one end of the shaft 11 or by me or lelical gears 19 and 20. A combines .iction and positiv is provided at the top of the sh =.rpose of conne ting the sh 15, the latter in turn i i he i the clutch soind ardly, it is out of clutching eng ;-mentwith the shaft 15 but rotates with the gear 20.- Qne or more springs or clutch member.) are secured to the clutch spindle, By pushing the clutch spindle downwardly for a portion of its travel frictional connection is first made between the clutch and the shaft 15 by means of the springs 22 and 22 pressing against an internal annular ridge of the shaft 15. This frictional engagement is desirable in order that the shaft he smoothly engaged. Further downward movement of the clutch spindle 21 eliminates the frictional connection as the springs 22 and 22 move into an annular recess 26 in the sh ft 15. At tlc same time, projection 2% on the clutch spindle comes into contact with a pin or projection on the upper end of the shaft 15 so that positive connection in made letweeu the clutch spindle 20 and the shaft 15 at fixed angular relation between these two members. This is necessary in order that the angular position of the drum 9 with respect to the shaft 17 can be predetermined and kept constant.

27 designates a tubular shafthaving' thereon a hand wheel 28 which is attached to the shaft 27 by means of a pin or key 29 which extends into a groove 30 in the shaft 27. This enables the shaft 2'? to be tinned or rotated by the hand wheel and at the same time allows the hand wheel to more ionizitudinally of the shaft 27 for aurpose which will presently appear. The plate is supported in fixed position by means of a yoke or anchoringmember 41 secured to the enlarged portion '27 of the shaft v27 and is in the slid-able relation to the guide members 42 of frame 1. The drum carrier 10 may therefore be raised and lowered by turning hand wheel 28.

An automatic feed mechanism is provided to turn the drum carrier a fraction of a revolution at every revolution of the drum 9. To this end the drum 9 has attached to tl top thereof a ring 31 adjustable around tl axis of the drum by means of set screws 31 and slots 31 which provide for aovancing or retarding the driving movement of the ring 31 as will appear. The ring 31 has a projection 32 which engages for a portion of a revolution with one or more tongues 3 which extend through guideways in the head. of the drum carrier 10. In Figure 5 the automatic feed is disengaged while in Fig; ure 6 the automatic feed is engaged. The feed mechanism is thrown i to and out of operation in the followim. When the with shown in Figure 5 to the eccentric position shown in Figure 6. The ton 'ues 33 are provided with upstanding pins or projections 37 which fit into an annular groove 35 in the guide 39. When the guide is in an eccentric po ition as shown in Figure 6, it causes one or more of the tongues 33 to project through the slots in the drum carri r so that at every revolution of the drum 9, the projection or lug 32 on the ring; 31 will engage for a fraction of a revolution with one of the tongues and thereby cause the drum carrier 10 to perform a partial revolution. he length of the path traveled by the projection 11,-! carrying with it the tongue 33 i i upon the degree of eccentricity o 39.

The direction of the threads 1 its proportional o than the norement 0" the drum car rier 10. As a result the upper end of the spindle 11 would eventually dome in contact with the hand wheel 28 nd would carrv the handwheel upwa dly with respect to the shaft 27. This action causes the pin 8. to move the guide 39 back to the conceniric position shown in Figure 5 and the automatic teed zi'icclianism is the shy disengaged when toe t um carrier has moved the limit of its travel. To acquire such a chart or record as shown in F g. 8 is the ultimate aim of the invention, and it follows that for each explosion oil the c nder. the piston 2 ot the device will move upwardly againstthe nut causing the pencil 8 to press against the record card a hereafter mentioned.

S nce the drum ii is rotating. say at camshatt speed. a line will be u'iade on the record card. the hangl'h or which will. denote the length oi time that the pressure in the cylinder is greater than the pressure of the spring 3.

At the beginning of the to the lower cud ot the drum 9. to other with the driun carrier 10 is at a pos ion about midw on the t aded po oi the indicator barrel 12. At the same me the lower end of the spring compressor ll, will be in such a position, relative to the in .icator barrel 12. so that very litttle pressure will be exerted on the spring 8. in other words, the spring 3 will be extended in length enough to reduce the pressure bearing on the flange of the piston 2. As the drum 12 rotates, (the automatic feed mechanism being in an eccentric position as shown in Fig. ('3) an explosion occurs in the cylinder of the engine and a mark or line is made on the record card, which will show the length of time that the cylinder pressure exceeds the spring pressure.

For each succeeding explosion the tension on the spring 3 is increasing and as a result the marl; wil become smaller and smallor until a point is reached in which the mark will be practically just a dot. During this time toe spindle or spring compressor 11 is slowly moving downwardly proportional to but less than the movement of the drum carrier 10. As a result the upper end of the spindle 11, eventually comes in contact with the handwheel 2S and carries the handwheel upward with respect to the shaft 27. As a result a series of marks made at regular intervals on the record card until the drum 9 and drum carrier 10 have reached the limit of their travel. will create a chart or record very similar to the one shown in Fig. 8,

It must be :turther carefully borne in mind that the member 11 is also non-rotatably mounted since it has a sliding fit by means of lugs 11 in slots 11* of the member 12.

The drive mechanism tending to rotate the rotatable parts'ot my device, either the gear 14. couin'uiuicatiug with the gear 13 or the handwheel 28, serves to rotate first the memher 9. No other portion of the recording means is rotated except when the handwhc 28 is pushed downwardly. the mo rent the pin 37 forcing the slides 2-33 with their carrier into a position eccentric ot the longitudinal axis ol the member 11. Then in this eccentric position as is tully disclosed in Figures 5 and 6, the slides 33 are in position to. be engaged tlnrough a partial revolution by the lug 32 on the rotating member 9. The engagement of the member 32 with the member Eli-3 will result in a partial rotation of the member 10. The member 10 having screw threaded engagement with the: member 12 will, by its rotatable movement be moved longitudinally thereof. Similarly its screw threaded portion 10 due to its rotatable movement will be moved longitudinally oi the member 11, but to a lesser degree since the pitch of the threads engaging with the member 11 is less than the pitch or the thread engaging with the member 19. This will cause a relative longitudinal and diiterential movement between the members 12 and 11. It should be understood that the member 39 does not rotate but merely e):- tends into the slot of the upper portion of the member 11, the members having lugs 35 adapted to be rotated around the circular guideway 35 clearly shown therein in Fig ures 5 and 6.

I claim:

1. An engine pressure recording instru ment embodying in combination, a rotary record card carrying drum, means for moving said drum in the direction. of its longitudinal axis. a piston operated. by engine pressure, a stylus operated by said piston, a yieldable resistance tor said piston, a movable tensioning member for va ryingthe force of said resistance, and diilerential gearing between. said drum and tensioning member for the purpose described.

2. An engine pressure recording instrument embodying in combination, a rotary record card carrying drum, intermittently operating means for moving said drum in the direction of its longitudinal axis. a piston operated by engine pressure. a stylus operated by said piston, a yieldable resistance for said piston, a morable tensioning 120 member for varying the force of said rcs' ance. and differential gearing between said drum and tensioning member for the purpose described.

3. An engine pressure recording in tru mentembodying in combination. a p operated by engine pressure. a st ius actuated by said piston. a rotary record card carrying drum driven by the engine, means for moving said drum axially. a yieldable liil) resistance element for said piston, a movable tensioning member for said resistance element, and connecting means between said drum and tensioning member whereby the latter is moved in a predetermined ratio to the axial movement of the drum and means controlled by said drum for actuating said tensioning member.

4:. An engine pressure recording instrument embodying in combination, a piston operated by engine pressure, a stylus actuated by said aiston, a rotary record card carrying; drum driven by the engine, means for moving said drum axially, a yieldable resistance element for said piston, a movable tensioningmember for said resistance ele ment, and means controlled by said drum for actuating said tensioning member.

5. An engine pressure recording instrument embodying; in combination, a piston operated by enq'ine pressure, a stylus actuated by said piston, a rotary record card carrying; drum driven by the engine, means for moving said drum axially, a yieldable resistance element for said piston, a movable tensioning member for said resistance element, means controlled by said drum for actuating said tensioning member, and means for automatically arresting the axial movement of the drum and the movement of the tensioning member after a predetermined travel of the drum.

6. An engine pressure recording instrument embodying in combination, a piston operated by engine pressure, a stylus actuated by said piston, a rotary record card carrying drum driven by the engine, a clutch for throwing the driving means into and out of gear, means for moving said drum axially,

yieldable resistance element for said pis ton, a movable tensioning member for said resistance elen'ient, and connecting means between said drum and tensioning member whereby the latter is moved in a predetermined ratio to the axial movement of the drum.

In testimony whereof I atiix my signature.

HAROLD CAMINEZ. 

